1. Field of the Invention
The present invention relates to integrated circuits. More particularly, the present invention relates to regulating the internal high voltage (Vpp) power supply in an integrated circuit memory device.
2. Description of the Prior Art
The programming voltage generated on-chip in an integrated circuit memory device is a function of the number of voltage multiplier stages used in the internal high voltage generator and of the voltage source (Vcc). Sometimes, the programming voltage can become greater than the breakdown voltages of some of the transistors in the high voltage circuits within the integrated circuit. When this breakdown voltage is exceeded, the memory contents may be disturbed. As a result, the reliability of any system incorporating such an integrated circuit is degraded. In a data processing setting, such lack of reliability may result in the loss of valuable information. Additionally, such excessive voltages may damage the integrated circuit or otherwise damage the equipment in which it is used.
The prior art approach to integrated circuit programming voltage regulation provides off-chip voltage regulation which increases parts, power, and circuit space requirements. Additionally, such off-chip regulation is subject to line interference and circuit transients which can adversely affect the accuracy and effectiveness of the regulator circuit.